ABSTRACT
A infusao de células hematopoéticas totipotentes criopreservadas permite a recuperaçao da hematopoese após quimioterapia mieolblativa. Objetivo. A formaçao de cristais de gelo durante o processo de congelamento é o fator principal que causa ruptura das estruturas celulares. A criopreservaçao dessas células a uma taxa constante preveniria os danos causados pelo congelamento brusco. Métodos. Vinte e três pacientes com mediana de 25 anos (variaçao 3-57) tiveram a medula óssea e/ou células-tronco periféricas (CTP) coletadas no período de março de 1993 a outubro de 1994, totalizando 86 congelamentos. Os pacientes apresentavam as seguintes neoplasias: linfoma nao-Hodgkin (n=5), leucemia mielóide aguda (n=8), leucemia linfóide aguda (n=6), doença de Hodkin (n=3) e mieloma múltiplo (n=1). O congelamento foicontrolado por um computador, acoplado ao sistema, às seguintes temperaturas: -1 graus Celsius/min até -45 graus Celsius e depois a -10 graus Celsius/min até -80 graus Celsius. Após o congelamento, as células foram mantidas em freezer a -110 graus Celsius até o momento da infusao. Para obtençao das CTP, empregou-se o fator de crescimento estimulante de granulócitos (G-CSF). Resultados. Uma mediana de 3,16 x 10(8) céls./kg (variaçao 0,86-24,22) de CTP e 2,03 x 10(8) céls./kg (variaçao 0,19-12,21) de medula óssea foi congelada. A mediana para atingir granulócitos maior ou igual a 500/muL e plaquetas maior que 20.000/muL foi de 12 dias (variaçao 8-40) e 31 dias (variaçao 8-80), respectivamente. Todos os pacientes tiveram recuperaçao hematopoética após a infusao das células criopreservadas. Conclusao. A criopreservaçao em congelador program vel permite o armazenamento de células hematopoéticas e, potencialmente, pode causar menor dano celular.
Subject(s)
Female , Humans , Child, Preschool , Middle Aged , Adult , Adolescent , Child , Stem Cells , Bone Marrow , Cryopreservation/methods , Transplantation, Autologous/methods , Freezing , Hematopoiesis , Neoplasms/drug therapy , Antineoplastic Agents/therapeutic useABSTRACT
UNLABELLED: The cryopreservation of hematopoietic stem cells can be used for rescuing the hematopoiesis after high dose chemotherapy. PURPOSE: The ice crystal formation during the freezing procedure is the key point that can be harmful to the cells. The cryopreservation of hematopoietic stem cells in a controlled-rate freezer could decrease the cell damage. METHODS: Twenty-three patients with a median age of 26 years (range 03-57) had bone marrow and/or peripheral blood stem cells harvested from March 1993 through October 1994, ending up to 86 freezing procedures. The patient's diagnoses are as follows: Non-Hodgkin's Lymphoma (n = 5); Acute Myelogenous Leukemia (n = 8); Acute Lymphocytic Leukemia (n = 6); Hodgkin's disease (n = 3); Multiple Myeloma (n = 1). The cells were frozen away in a controlled-rate freezer chamber at the following rate: -1 degree C/min from room temperature to -45 degrees C and then, at -10 degrees C/min down to -80 degrees C. After freezing, the cells were kept into mechanical freezers until the marrow infusion. To mobilize PBSC (peripheral blood stem cells), G-CSF (granulocyte colony stimulating factor) was given. RESULTS: A median of 3.16 x 10(8) cells/kg (range 0.86-24.22) of PBSC and 2.03 x 10(8) cells/kg (0.19-12.21) of bone marrow cells were frozen. The median time to reach granulocytes greater than 500/microL and platelets greater than 20,000/microL was 12 days (range 8-40) and 31 days (range 8-80), respectively. All patients had marrow engraftment after infusion of hematopoietic stem cells. CONCLUSION: The cryopreservation procedure using a controlled-rate freezer can store hematopoietic stem cells and potentially, cause less damage to the cells.